There are many types of welding power supplies used for a variety of welding processes. Welding power supply typically includes a wire feeder, a power source, a torch or gun, a wire feeder controller, and a power source controller to control the various components. These components of the welding power supply may share a housing, or be encased in separate housings. The power source of the welding power supply typically includes the power circuitry of the welder (e.g., rectifiers, switches, transformers, SCRS, etc.) that process and provide the output power of the welding power supply. The power source controller of the welding power supply typically includes digital and/or analog circuitry, discrete and/or integrated circuitry, microprocessors, DSPS, etc., software, hardware, and/or firmware which are used to control a welding process, or a device such as a power source and/or wire feeder.
Arc welding power supply sources used for MIG welding normally include at least two welding controls. One of the welding controls is for control of arc voltage and the other welding control is for control of wire feed speed. It is not uncommon for the MIG welders to include additional controls to enable more precise control for the welding process. Indeed, some welding applications are so demanding that the welding power source includes several welding controls to achieve the required results for a particular welding application. There are, however, many “simple” welding applications which do not require precise control for the welding process. MIG welders that are designed for such applications include fewer welding controls and are typically priced lower than the more complex models. Although these welding machines designed for simple welding applications are less complex in design, these welding machines still include a plurality of welding controls for the arc voltage and/or current level of the output current of the welder and for wire feed speed. As a result, these welding controls must be properly selected in order to obtain an acceptable weld in even these simple welding applications. The required setting of two or more welding controls adds additional complexity to a welding process and increases the incidence of an improper weld being formed for a particular application.
In view of the prior art, there is a need for an arc welder that is low cost, that is simple to operate and which generates a desired current level for a particular wire feed speed by use of fewer user controlled inputs.